Machine for molding tubes.



W. NORRIS.

MACHINE FOR MOLDING TUBES.

APPLICATION HLED MAY 22. 1914.

1, 182, 1 99, Patented May 9, 1916.

2 SHEETS SHEET I.

W. NORRIS. MACHINE FOR MOLDING TUBES.

l Be it-known that I, WEBs'mR UNITED STATES PATENT OFFICE.

WEBSTB NORRIS, OF NORTH BBOOKFIELD, MASSACHUSETTS, ASSIGNOB TO THE B 8c 3' RUBBER COMPANY, OF NORTH 'BBOOKFIELD, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

Application filed Kay 22, 1914. Serial No. 840,841.

To all whom it may concern Nouns, of North Brookfield, in the county of Worcester and State of Massachusetts, a citizen of the United States, have invented a new and useful Improvement in Machines for Molding Tubes, of which the following is a specification.

Pure rubber or caoutchouc is mixed with a variety of materials for vulcanizing purposes and also with other substances to secui'e certain physical qualities in the resulting material.

The mixing isefl'e'cted' usually by a air of rolls driven at unequal speeds to pro uce a grinding action so that the various constituents will become incorporated into a more or less homogeneous plastic mass, this rocess usually working considerable air into the mixture-which should be eliminated before vulcanization in order that the finished product may not i the air in pockets.

to occur.

4 In formmg rubber tubes, especially where they are made of a compound comparatively low in rubber, this is particularly apt Moreover, such tubes usually come out from the tubing machine with a more or less roughened outer surface.

The use of my tubing machine herein described has resulted in an improved product,and while I have shown therein my inend of a tubing ventlon in its best form, it will be apparent that it may be otherwise embodied and it may beusedin molding other plastic materials. 1 It will be understood by reference to the drawings, in which- Figure 1 is alongitudinal section of the machine show' my improvements. Fig. 2 is a plan an Fig. 3 a elevation of the. compression collar.

I have shown only enough the usual cylinder and feed to explain the improvement which comprises my nvention,

rotating feed. screw by which the gumwhich is put into a hopper (not shown) at the farther end of the cylinder in pressed out through the die.

Just beyond which contains that part of the chamber a Specification of Letters Patent.

be blistered or hold v A being the cylinder of the tubing machine and B the the screw B the diameter of momma ron moLmNe Tunas.

Patented May 9, 1916.

the chamber a is increased to form a shoulderlc against which a s ider or bridge 0 is held by a screw rin a portion of this part of the interior iein threaded forthe purpose and the ring being provided with recesses for a spanner by which it is screwed in place.

' The bridge 0 is provided with 'a central threaded opening a into which the central s indle D screws. This spindle is of two dlarneters to form a shoulder as at 11 against which the compressor collar E abuts, this collar having a central opening therethrough also of two diameters so as to form a shoulder e which will engage the shoulder d of the spindle. The pressure of the materlal passing through the machine holds the collar in place against the shoulder d.

The chamber a is furtherincreased in diameter to form a chamber a of enlarged dlameter partially closed by the collar E and the diameter of the collar E is so proportioned to the internal diameter of the cylinder A as to leave a comparatively narrow passage 0 through which the rubber stock will be forced so as to squeeze out of a it or hold back any air which may be car- 7 that the desired result will be secured without increasing friction. It thus passes into the chamber a which is'between the collar E and the die F.

The outer end of the spindle D is provided with a threaded recess J into which is screwed the mandrel D w This mandrel is centered by the spindle D in a die F of peculiar construction, its peculiarity being that it provides a conical passage f for the stock which terminates in an edge f after which the passage imme diately increases diameter as at f and ends abruptly. The finishing of the tube is therefore the result of the contact of the material-with this edgev f whichforms it into a tube of pro er diameter and thickness and immediate y the tube is freed from any further contact with the die.

The die F is held in the machine by a die holder F into which it screws and which is held against a shoulder a near the end of er l, the 99m iha ianr1 the cylinder A by the threaded binding ring F, the die holder being first centered by the set screws i so that the passage f between the mandrel and the edge f will be of equal the material is fed into the hopper and carried along by the feed screw in the chamber a, and then'through the bridge C and the passage through the ring and around the p d D h t kin the ar E it i pushed from behind up the incline e to the P s g thro g i h it is iammeith s q iri g a thi kne s a .p ex ht g th i kn s a h finished he- T heet;- ing action upon material as it asses through the passage (1 tends to squeeze out rom it an hir w i h it a phte h a hold the air back-sothat it will not pass into the chamber a or if it does it will be pa t m he me el ialr m the m er f s fli d t ro gh he QQlQ P s e f W ic gradu y molds it as it ha s until it r a hes a Pass s h ed A f when the confining pressure is inane 1- tab ed an h ished pr dh t t e' t r vu ca iz hgr t i d nt th h tqihp essor ce la while a desirable feature need not necessarily be used in connection with the die, the i i g u e ul ith a f rm of tubing in n the l ar be ng he usef in other mechiha r t eating rubbe 9 o h r pl t material M eve t may we $1 .1 p ed he W a wi se m t t ese i ed in the a 9: 9 man a im t. he e o m d g t r be or rh hsr 9i poun s.

Other wa of e h trh ih and emh hhg e ea ur s f my mas hih 'w ll 9m e e ski e ia'the V, ha 1 cla m as a invehtiq is 1 1 ma h ne a treh m plas t aerihl the ee hhiaetieh wit ga m a- .15 e eams h the te ial ad an o let at h eh' he mate i l -s amed a h compressor or'squeezing the out of the Plast me ereh. hi qh ares .Ze ng 1 et si a wt t tshng'meana and and 01] e a ti biomah t a has der tame. a 1 a teed. hrew 1M DQTHQQ a 9 amber 9? W 9: 9 L a; in nother Pat es Qt al amb r. id eht ht at 211 Said ta i e ewa a s a l a P an heater he to t so as leave an annular aperture between said compressor collar is located.

3. In a machine for treating plastic material, the combination with a hollow cylinder having a chamber, of a feed screw in a portion of said chamber, a conical compressor collar in another portion of said cham her and concentric with said feed screw, said o r ha ng a d t r e than sa chamber so as to leave an annular aperture wee the berihh y of a colla and the wall of said chamber, and a" outlet from sa hamb r h 'h t hh' whlh hhtle and d ed at! ei e hp tsse seller is located. 4. In a. tube molding machine, the combit n" w h =1 h ll 'I yl h r h ih a amb a a t ng m ans i sa h m l forieeding in plastic material, a die mandrel affording an outlet from said mb r nd a c mures in te l n h amber bve v h aid orc ng feedihg me n and said butlet.

5. In a tube molding maclgine, the combihmhe a t d sq n h tehhf said ham r a ma dr le d e a fqr ihg a dischar e out et from said chamber, an a com ressor col ar in said chamber between said ee ing screw and said mandrel and (lie, ai ce a ei g wateht wi h a ih s ew ahd'h h a a ete less thhh t 'd em ret ha i ti h of the chamber in which it is located, so as to leave an annular o ening between the periphery m h 59h he at a c ar an, the

' l r. %E,.BST.E..R NORRIS Witnesses 

